


// #iChannel0 "file://lv_1.png"
#iChannel0 "file://home_bg.jpg"


// iResolution  已知
// iTime 已知
void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
    float curdis = 0.1;

    vec2 st = fragCoord/iResolution.xy;

    vec2 tapPoint = vec2(iMouse.x/iResolution.x,iMouse.y/iResolution.y);

    vec3 color = vec3(0.0);

    //  fragColor = texture(iChannel0, st);

     vec2 dv = tapPoint - st;
    dv = dv * vec2(iResolution.x/iResolution.y, 1.0);
    float dis = sqrt(dv.x * dv.x + dv.y * dv.y);
    float disF = clamp(0.3 - abs(curdis - dis), 0.0, 1.0);
    vec2 offset = normalize(dv) * sin(dis * 100.0 + iTime * 10.0) * 0.1 * disF;
    vec2 uv = st + offset;
    fragColor =  texture(iChannel0, uv);
}